kvm/x86: Hyper-V kvm exit
A new vcpu exit is introduced to notify the userspace of the
changes in Hyper-V SynIC configuration triggered by guest writing to the
corresponding MSRs.
Changes v4:
* exit into userspace only if guest writes into SynIC MSR's
Changes v3:
* added KVM_EXIT_HYPERV types and structs notes into docs
Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 88af846..053f613 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -3337,6 +3337,28 @@
it is still asserted. Vector is the LAPIC interrupt vector for which the
EOI was received.
+ struct kvm_hyperv_exit {
+#define KVM_EXIT_HYPERV_SYNIC 1
+ __u32 type;
+ union {
+ struct {
+ __u32 msr;
+ __u64 control;
+ __u64 evt_page;
+ __u64 msg_page;
+ } synic;
+ } u;
+ };
+ /* KVM_EXIT_HYPERV */
+ struct kvm_hyperv_exit hyperv;
+Indicates that the VCPU exits into userspace to process some tasks
+related to Hyper-V emulation.
+Valid values for 'type' are:
+ KVM_EXIT_HYPERV_SYNIC -- synchronously notify user-space about
+Hyper-V SynIC state change. Notification is used to remap SynIC
+event/message pages and to enable/disable SynIC messages/events processing
+in userspace.
+
/* Fix the size of the union. */
char padding[256];
};